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PubMed2003

The structure of body measurements for the determination of shoe sizing for young Croatian men.

The determination and promotion of the system of shoe sizing requires accurate knowledge of morphological properties of the foot and lower leg of the tested population. Similarly it is necessary to establish the occurrence and regional distribution of definite sizes in the tested population. Possible regional differences in morphological properties must not be ignored because it has been established by means of anthropological measuring that both foot dimensions and foot shapes differ between populations and within the same population. This has been proven by the investigation of body measures, carried out for the purpose of establishing a system of footwear sizes, which was executed on a randomly selected sample of 4,268 healthy and normally developed males aged 18-22. The investigation was carried out in 1993 on five locations each of which representing a definite region of the Republic of Croatia: Jastrebarsko (central), Koprivnica (northwestern), Pula (southwestern), Sinj (southern) and Pozega (northeastern). The measuring instrument was 31 foot and lower-leg sizes according to the existing ISO standards for footwear. Interregional differences are significant in all body measures. The role and the contribution of individual measures to these differences has been established by means of discriminatory analysis with regions as a priori defined samples. In order to constitute a convenient and purposeful standard for the footwear size system it is necessary to work out a database with referent values for the same system.

Adolescent↗
PubMed1998

High-resolution DNA fingerprinting of parthenogenetic root-knot nematodes using AFLP analysis.

Amplified fragment length polymorphism (AFLP) analysis has been used to characterize 15 root-knot nematode populations belonging to the three parthenogenetic species Meloidogyne arenaria, M. incognita and M. javanica. Sixteen primer combinations were used to generate AFLP patterns, with a total number of amplified fragments ranging from 872 to 1087, depending on the population tested. Two kinds of polymorphic DNA fragments could be distinguished: bands amplified in a single genotype, and bands polymorphic between genotypes (i.e. amplified in not all but at least two genotypes). Based on presence/absence of amplified bands and pairwise similarity values, all the populations tested were clustered according to their specific status. Significant intraspecific variation was revealed by AFLP, with DNA fragments polymorphic among populations within each of the three species tested. M. arenaria appeared as the most variable species, while M. javanica was the least polymorphic. Within each specific cluster, no general correlation could be found between genomic similarity and geographical origin of the populations. The results reported here showed the ability of the AFLP procedure to generate markers useful for genetic analysis in root-knot nematodes.

Animals↗
PubMed1988

Analysis of the molecular basis of HLA-A3 recognition by cytotoxic T cells using defined mutants of the HLA-A3 molecule.

The structure-function relationships in human class I HLA molecules have been examined by the analysis of two T cell-defined subtypes of HLA-A3 (A3.1 and A3.2). These subtypes differ by two amino acid residues that are located at positions 152 (GluA3.1 vs ValA3.2) and 156 (LeuA3.1 vs GlnA3.2). By the methods of site-directed mutagenesis and DNA-mediated gene transfer, mammalian cell transfectants have been produced that express only one of the above A3.2 amino acid residues at either position 152 or position 156. Previous studies using murine transfectants have shown that A3.1- and A3.2-expressing cells can be distinguished by A3.1-restricted type A influenza virus-specific CTL and A3.2-allospecific CTL and have implied that amino acid position 152 plays a key role in this specificity. To test whether these results were a function of the virus specificity, the alloantigen, or the cell type expressing the class I molecules, we have tested the recognition of human and murine cell transfectants by A3.1-restricted, A/JAP/305/57 and B/Ann Arbor-specific CTL and by A3.1- and A3.2-allospecific CTL. The results indicate that the Glu at position 152 is critical for recognition by all of the A3.1-restricted CTL populations tested and 15 of 16 of the A3.1-allospecific CTL populations tested. The A3.1 Leu at position 156 was sufficient for recognition by only one A3.1-allospecific CTL line. Substitution of the charged Glu residue for the polar Gln at position 156 of A3.2 affected recognition of some but not all A3.2-alloreactive CTL. These data demonstrate that the structural basis for epitopes that are recognized by almost all CTL that discriminate between A3.1 and A3.2 is primarily the amino acid at position 152. The implications of these data for Ag presentation and CTL recognition are discussed.

Adult↗
PubMed2004

An 8-year experience in airborne contact dermatitis.

OBJECTIVE: A large number of case reports concerning occupational airborne contact dermatitis have been published in the last few years. Our purpose was to establish the prevalence of airborne contact dermatitis in a routinely patch-tested population and to obtain further epidemiologic data. METHODS: In a single-center study, the data of 5,092 routinely patch-tested patients were collected using a standardized questionnaire and a documentation form. The study period extended from October 1994 to March 2002. RESULTS: The clinical diagnosis was airborne contact dermatitis in 15 cases (0.29%). Patch testing revealed positive and relevant results in nine patients (0.18%). Plant or wood extracts were the sensitizers in all cases but two, and perfume and epoxy resin were the sensitizers in one case each. The diagnosis of an irritant airborne contact dermatitis was established in six patients. A relationship with occupation was found in seven cases (0.14%) when 'housewife' was included as an occupational category and in five cases (0.1%) when this was excluded. CONCLUSION: Airborne contact dermatitis is a rare diagnosis in an unselected patch-test population. An occupational relationship was less common than has been implied in case reports in recent years.

Adolescent↗
PubMed1989

Diagnostic and prognostic value of exercise electrocardiography for coronary artery disease.

A positive exercise ECG with greater than or equal to 1.0 mm ischemic ST-segment depression, limited exercise duration, persistence of ischemic ST-segment depression past 8 minutes in the recovery period, and exertional hypotension is associated with increasing severity and extent of CAD. The sensitivity and specificity of the exercise ECG are not dependent on the prevalence of CAD in the population tested. The positive and negative predictive values of the exercise ECG are both dependent on the prevalence of CAD in the population tested. Exercise-induced ST-segment elevation greater than or equal to 1.0 mm is associated with severe myocardial ischemia, left ventricular aneurysm, left ventricular wall motion abnormalities, and coronary artery spasm in patients with variant angina. Ischemic ST-segment depression greater than or equal to 1.0 mm, exercise duration, maximal exercise heart rate, and blood pressure response to exercise are correlated with new coronary events in patients with documented CAD. Low-level exercise tests within 3 weeks of uncomplicated MI can identify patients at high risk for new cardiac events. Early post-MI patients with exercise-induced ischemic ST-segment depression greater than or equal to 1.0 mm, exercise-induced angina, an inadequate blood pressure response to exercise, or limited exercise duration during a low-level exercise test should undergo coronary angiography and be considered for possible coronary artery surgery or angioplasty. Exercise testing will also help in the medical treatment of patients with exercise-induced angina or malignant ventricular arrhythmias. An exercise test performed 6 months after MI also provides prognostic information not available from clinical evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2002

Testing for population subdivision and association in four case-control studies.

Population structure has been presumed to cause many of the unreplicated disease-marker associations reported in the literature, yet few actual case-control studies have been evaluated for the presence of structure. Here, we examine four moderate case-control samples, comprising 3,472 individuals, to determine if detectable population subdivision is present. The four population samples include: 500 U.S. whites and 236 African Americans with hypertension; and 500 U.S. whites and 500 Polish whites with type 2 diabetes, all with matched control subjects. Both diabetes populations were typed for the PPARg Pro12Ala polymorphism, to replicate this well-supported association (Altshuler et al. 2000). In each of the four samples, we tested for structure, using the sum of the case-control allele frequency chi(2) statistics for 9 STR and 35 SNP markers (Pritchard and Rosenberg 1999). We found weak evidence for population structure in the African American sample only, but further refinement of the sample, to include only individuals with U.S.-born parents and grandparents, eliminated the stratification. Our examples provide insight into the factors affecting the replication of association studies and suggest that carefully matched, moderate-sized case-control samples in cosmopolitan U.S. and European populations are unlikely to contain levels of structure that would result in significantly inflated numbers of false-positive associations. We explore the role that extreme differences in power among studies, due to sample size and risk-allele frequency differences, may play in the replication problem.

Case-Control Studies↗
PubMed1998

Contact hypersensitivity to tixocortol pivalate.

BACKGROUND: Tixocortol pivalate is an established marker to topical corticosteroid allergy. The prevalence of tixocortol pivalate hypersensitivity is well established in Europe, where exposure to this corticosteroid as a therapeutic agent varies. In the United States, tixocortol pivalate is not commercially available and the prevalence of hypersensitivity to it is unknown. OBJECTIVE: We investigated the prevalence of tixocortol pivalate hypersensitivity in our patch-tested population. We further characterized these patients by clinical background, other contact allergens, and the reactivity to other corticosteroids. METHODS: Tixocortol pivalate has been incorporated in our standard 1-52 patch test series since November 1992. We reviewed the histories and patch test results in all patients tested with the standard 1-52 series from November 1992 to December 1996. RESULTS: Of 1536 patch-tested patients, 45 had hypersensitivity to tixocortol pivalate. Dermatitis involving the face was the most common (14 patients). Of the 45 patients, 40 had another allergen identified on patch testing. Eighteen patients underwent further patch testing to an extended corticosteroid panel, and 14 had sensitivity to another steroid agent. CONCLUSION: The 2.9% prevalence of tixocortol pivalate hypersensitivity in our patch test population is within the range reported in Europe. Patients with tixocortol pivalate hypersensitivity tend to have other contact allergens on patch testing. Predisposing factors to tixocortol pivalate hypersensitivity include facial dermatitis and sensitivity to other contact allergens.

Administration, Topical↗
PubMed1985

Resistance to adenovirus infection after administration of Bordetella pertussis vaccine in mice.

Treatment of mice with Bordetella pertussis vaccine rendered mice resistant to mouse adenovirus infection. The resistant state took at least 5 days to develop, and susceptibility returned to a portion of the test population 35 days after treatment. Transient resistance developed in congenitally athymic mice also. Treatment with a dose of 25 micrograms (dry weight) of B. pertussis vaccine protected approximately 50% of the test population. Vaccines prepared from several different strains of B. pertussis were capable of inducing resistance, and the induction of resistance was not dependent on the mouse strain used for testing. Cross-reacting antibodies capable of neutralizing the virus or protecting against a challenging infection were not induced by treatment with B. pertussis vaccine.

Adenoviridae Infections↗
PubMed1976

X-ray-induced recessive lethal mutations in the mouse.

A test of X-ray-induced recessive lethal mutations in mouse spermatogonia (500 rad) was carried out. The test was based on familial analysis, which allowed division on the P pairs into those with lethal heterozygous members and in others assumed to be lethal-free. The F1 males from the latter group, in back-crosses to their daughters, gave an excessive rate of intra-uterine death in comparison with lethal-free males. The excessive death is assumed to reflect the rate of new (induced + spontaneous) recessive lethals or rather lethal equivalents. Three ways of estimating the rate of new recessive lethal mutations gave a mean of 5.5% per genome. From the previous tests we can assume that 1% are spontaneous mutations. Thus the data indicate that the mutation rate per rad per gamete is 9 X 10(-5). This value is identical with a previous estimate. The results are discussed in relation to population tests performed in the early 60's. It is concluded that the lack of observable deterioration in the populations after several consecutive generations of exposure is in accord with the estimates in the present analysis which are more than an order of magnitude lower than assumed at the start of the population tests. It is also stressed that species with different DNA contents show similarities in point estimates of doubling dosages.

Animals↗
PubMed1999

Prevalence of diabetes in Catalonia (Spain): an oral glucose tolerance test-based population study.

The goal of this study was to investigate the prevalence of diabetes mellitus and impaired glucose tolerance in the adult population of Catalonia and study their association with obesity, central obesity, hypertension and smoking habit. A random sample of 3839 subjects aged 30-89 years participated in this cross-sectional study: 2214 subjects underwent a health examination with oral glucose tolerance test (OGTT) and 1625 were interviewed by phone. Diabetes prevalence (known and unknown) in the 30-89-year-old population was 10.3%, (95% CI: 9.1-11.6). In this age group, the prevalence rates of known diabetes, unknown diabetes and impaired glucose tolerance were 6.4, 3.9 and 11.9% in men and 6.9, 3.4 and 11.9% in women. The age adjusted prevalence to the world population for the 30-64-year-old age group was 6.1% (7.1% in men and 5.2% in women).The factors significantly associated with diabetes were age, obesity, hypertension and family history of diabetes. The high ratio of previously known diabetic cases to newly discovered ones, specially in the oldest age group, suggests good levels of awareness and medical services. The prevalence in Catalonia is similar to that observed in other Mediterranean countries.

Adult↗
PubMed1999

The effect of Leishmania major on some biological parameters of Phlebotomus papatasi (Diptera: Psychodidae) from endemic and non-endemic areas in Egypt.

Biological activities of two populations of Phlebotomus papatasi collected from two different areas in Egypt (Sinai and Aswan) and the effect of Leishmania major on such activities were investigated under insectary conditions. A significant reduction (P < 0.05) was observed in the number of eggs laid by the infected females when compared to the non-infected females of the tested populations. The immatures of the Aswan population required a longer period (P < 0.05) to complete larval development. Life expectancy at emergence for infected and non-infected females was almost 13 days for the two populations. No significant difference was observed for the effect of L. major on the survivorship of tested populations. The mean generation time for the non-infected and infected females of Sinai and Aswan were 47.5, 49.8, 50.8, 49.5 days, respectively. Mean productivity (the number of females produced by one female) of the non-infected females of the Sinai population (18.1 female female/female) was significantly higher (P < 0.05) than the Aswan population (12.3 female female/female) while the productivity for infected females for both Sinai and Aswan populations (10.8 and 7.3 female female/female) was significantly reduced (P < 0.05). These results show Leishmania infection affects the fertility and productivity of both populations and may be a factor in controlling the insect population size in nature.

Animals↗
PubMed2003

Value of self-reportable screening criteria to identify asymptomatic individuals in the general population for urogential Chlamydia trachomatis infection screening.

Submission of samples from the home allows screening for Chlamydia trachomatis without preceding professional assessment of clinical risk factors. Therefore, a validation of self-reportable information for use as selective screening criteria is needed. We asked a total of 1175 women and 1033 men who participated in an in-home sampling screening study to provide information on behavior and sociodemographic characteristics. In a multivariate model, selective screening criteria were developed on the basis of information from a random part of the tested population (development group), and the validity was assessed for the remaining part of the tested population (validation group). To find all infections, 95% of the subjects had to be screened, and screening 63% of them would have detected 86% of infections. Low predictive values were found when selective screening criteria from other studies were assessed. Selective screening by means of in-home sampling strategies among men and women aged 21-23 years cannot be recommended in the area studied.

Adult↗
PubMedDate not supplied

The effect of disease-prevalence adjustments on the accuracy of a logistic prediction model.

The accuracy of a logistic prediction model is degraded when it is transported to populations with outcome prevalences different from that of the population used to derive the model. The resultant errors can have major clinical implications. Accordingly, the authors developed a logistic prediction model with respect to the noninvasive diagnosis of coronary disease based on 1,824 patients who underwent exercise testing and coronary angiography, varied the prevalence of disease in various "test" populations by random sampling of the original "derivation" population, and determined the accuracy of the logistic prediction model before and after the application of a mathematical algorithm designed to adjust only for these differences in prevalence. The accuracy of each prediction model was quantified in terms of receiver operating characteristic (ROC) curve area (discrimination) and chi-square goodness-of-fit (calibration). As the prevalence of the test population diverged from the prevalence of the derivation population, discrimination improved (ROC-curve areas increased from 0.82 +/- 0.02 to 0.87 +/- 0.03; p < 0.05), and calibration deteriorated (chi-square goodness-of-fit statistics increased from 9 to 154; p < 0.05). Following adjustment of the logistic intercept for differences in prevalence, discrimination was unchanged and calibration improved (maximum chi-square goodness-of-fit fell from 154 to 16). When the adjusted algorithm was applied to three geographically remote populations with prevalences that differed from that of the derivation population, calibration improved 87%, while discrimination fell by 1%. Thus, prevalence differences produce statistically significant and potentially clinically important errors in the accuracy of logistic prediction models. These errors can potentially be mitigated by use of a relatively simple mathematical correction algorithm.

Adult↗
PubMed1990

[Biphotonic absorptiometry of the foot: methodology and application to algodystrophy].

A simple methodology for the evaluation of the bone mineral content of the foot by biphotonic absorptiometry is described. From the study of a test population, a pathological demineralization threshold of 10%, given that the measurement is expressed in g, has been defined at the level of the forepart of the tarsus. This threshold enables the significant distinction between the test population and a population with algodystrophy. Biphotonic absorptiometry seems to provide a quantitative diagnostic argument to complement the radiographical and scintigraphical examinations.

Absorptiometry, Photon↗